Problems with new Oil fired central heating system

Hi, I received a grant for a new oil fired heating system. It was installed about 1 month ago. Since then it have been making noises that I think are called kettling. The water in the pipes rumbles in the tank in the loft and also when the hot water tank on the first floor fills. It is so noisy it seems like the whole thing could fall through the ceiling!

It seems to be an F& E system. How do I get it to settle down. Is it air locked and if so how do I solve this problem. The system hasn't been signed off as yet. The grant provider's auditor will call on Monday to sign it off. Want to know what I am talking about to him before I tell him about the problem.

This has been happening from the first day the system was turned on. There was also a problem in that the pipes from the oil tank to the boiler were leaking kerosene. Called contractor and they fixed this. The hot tap in the bathroom was running slow but this has also been fixed by the contractor. Are these problems related?

The rumbling or kettling in the system happens on the hour after the system switches itself on-you could almost set your watch to it! Any advice would be appreciated.

Many thanks